Drill pipe protector



W. G. L. SMITH DRILL PIPE PROTECTOR Flled May 19, 1941 l June 19, 1945.

Patented June 19, 1945 Walter G.I L. Smith, lLos Angeles,` Calif., assigner to `Thermod Company, Trenton, N. J., acorporation of Delaware `ApplicationMay 19, 1941,` Serial No. 394,145 6 Claims.` `(01,; 308-4) This 'inventionrelates to drill pipe protectors `for use o n sections of astring vof well drilling pipe to protect the pipe from Wear against the Wellcasing or the side Walls of the well in the operation of a rotary Well drilling rig.

It `has been'customary'tomake the drill pipe protectors in the form of rings of rubber or other resilient material and to secure them upon the pipe in positions xed both longitudinally and circumferentiallyl ofthe pipe. It is of obvious advantage toprevent movement of the drill pipe rprotector longitudinally of the pipe as otherwise the" protector under the action of gravity `will move downward to the nearest coupling. 'The disadvantage of a circumferentially iixed mounting of the protector upon thedrill pipe has been recognized.' The drill pipe in rotary drilling is slowly rotated on its'axis. A protector circum'- ferentially "xed upon it,.when thrown by` the pipe` against the sides of the well, is subject to a glancing blow whichis obviously moredestruc tive of theprotector than is a blow delivered perpendicularly to the `protector with no tangential component. `Even when the drill pipe is not rotated, if it swings outwardly throwingthe protector against the sides of the well, it isapparentfthat either because of irregularities in the surfacecf the sidewalls of the well or 'be`` cause theprotector may be thrown at an `angle i neath the ring and of having an ineffective shortlived longitudinal retaining means.

Itis one object of the invention to provide a `drill pipe protectorwhich will stand up under the heavy blows to which it is subjected.

Itis another object of the invention to provide in a practical form a rotatable resilient protector.,

It is another object of the invention to provide a protector which will be both longitudinally stationary and circumferentially rotatable with respect tothe pipe.

It is another object of the invention to provide in a ,rotatable drill pipe protector,`a bearing for thefrotating ring or spinner into Which the mud fluid cannot enter to drill pipe. e It is another object ofthe invention to provide a drill pipe protector` which is held stationary longitudinally of the pipe bymeans `of a relatively stretehable resilient inner annular element shrunk on the pipe and which protector takes blows against the sides of the Well by means of a relatively hard rubber ring carried by the inner annular element on the drillpipe.

It is another object of the invention to provide a convenient method lforfassembling in position upon the drill pipe a drill` pipe protector comprising two members, an inner annular resilient body adapted to be shrunk on the pipe and an outer annular 'resilient body rotatively mounted cut through the wall of the in longitudinally fixed position upon the innerK ring. e

In the drawing, which` is for illustrative purposes onlyz` e i Fig.` 1 isa perspective view of a drillppe protector embodying` this invention shown in assem-` forthe mud uid used in the drilling operation andthismud fluid cuts through the drill pipe withfextreme rapidity. The second difficulty lies will stand up under the severe conditions which obtain in a well ation. V i i i f A drill pipe protector of this invention has the during the well drilling loperadvantages attendantupon a rotative resilient e' ring and has notthe disadvantages er being the cause of 'a rapid cutting of the pipe radially be- 55 bied position upon asetion of drm pipe, thenrm pipe being shown in fragmentary view; e e f Fig. 2 is a longitudinal section of the protectorA and pipe section shown in Fig. l;

Fig. 3 is a longitudinal section-of the base of the drill pipeprotector;

Fig.` 4 is an end View of the base;

Fig. 5 is a longitudinal sectionalview ofthe itotatable ring or spinner of the drilllpipe protec` Fig. 6` is anendview of the spinner;

Fig. '7 `is alongitudinal sectional view ofthe base of `the drill pipe `protector shown on a-storage orhandlingmandrel; t i

l Fig.` 3 `is va longitudinalwsectional 'view of the pirlmervshownton a storage `or handling manre;M

Fig. 9 is a longitudinal sectional view oi a modined form of the drill pipe protector of this invention;

Fig. is a longitudinal sectional view of another modified form of a drill pipe protector of this invention; and

Fig. l1 is a longitudinal sectional View of still another modification of the invention.

A drill pipe protector of this invention generally designated by the numeral II comprises a base I2 and a spinner I3.

` holder 25, the holder being formed of thin-walled The base I2 is preferably a one-piece block of rubber or other like resilient material having a central bore I6 and a cylindrical outer face I5. An annular groove or slot I4 disposed centrally of the blockextends inwardlyfrom the outer' cylindrical surface I5 of the block partway toward the bore surface I6. The annnular slot I4 provides end flanges I'I and a central neck` I 8.V

'ner VI 3 is slightly less than the length of the slotr I 4.

Both the base I2 and the spinner I3 are preferably manufactured in accordance with the invention which isthe subject matter of an application for patent by Adelbert M.*Graharm, Serial No.,389,759, filed April 22, `1941. In accordance withxthe invention of that application, one-piece cylindrical rubber pipe protectors are made by spirally winding upon a mandrel a thin sheet of hot compounded uncured rubber taken directly from the final roll of a calender roll machine. The laminated cylinder thus formed is cured on the mandrel in a vulcanizing Afurnace and while still on the mandrel is turned down to the proper diameter and cuttovthe properV length. It is then removed from the mandrel and upon removal `shrinks to a slightly smaller diameter Iboth as to itsl bore and its outer cylindrical surface. The molecules of each lamina are in'a condition to set up circumferential Astresses tending to still further shrink the protector as toits diameter andthe laminae arebonded to each other by an adhesive relationship,v resulting from the superimposing ofthe spiral convolutions While in a 4`:In using the method ofthe invention disclosed therein disclosed. In making the base I2', the invention ismodiiied by moving separator knives or bladesup to the firstcalender roll against which the rubber stock is thrownafter the base is built up to the diameter of the neck I8. These separator knives or blades Yare spaced from each other an interval equalto the length of the groove I4 and are placed at points along the calendervroll corresponding to end walls 24 of the groove I4 (see Fig. 3). The rubber stock is then thrown against the calender roll between the separator blades andthe end of the base to form the flanges The finely spaced lines 34 ron the drawing `indicate the bonding joints lbetween laminae.l

y The base I2 is expanded by means of a machine such as is shown in the application of Adelbert M. Graham,y Serial No. 346,615, filed. July v 20. 1940, and transferred to a storage or handling mandrel which may be for convenience termed a holden such as is also described inapplication Serial No. 346,615 of Adelbert M. Graham. In Fig. 7 the base is shown thus mounted on a pipe. By comparing the base as shown in Fig. 7 with the base as Shown in Fig. 3, it will be observed that the inside and outside diameters of both the flanges and the neck have been greatly increased, the wall thickness and the length of the flanges have been decreased,y and the neck I8, due to its thin wall, has buckled and shows one or more folds between the flanges.

The spinner I3 is similarly expanded and placed upon a holder 26 of a larger diameter than the holder 25. l The base and spinner are now ready for assembly upona section of drill pipe.

During the drilling operation and after the kelly'has been disconnected from the uppermost section'of the drill pipe or when the pipe sections are on a pipe rack or otherwise disposed singly or in double or treble stands, the holder 25 with the base I2 mounted thereon istelescoped` over one end of the section of drill pipe together with hydraulic means assembled with the holder 25 such as is shown in the above mentioned application Serial No. 346,615-of Adelbert M. Gra.- ham. The holder 25V has a bore of sufcientsize to pass over any sleeve coupling or tool joint which may be secured to the drill pipe. A frag mentary view'lof a pipe section 21 lis shownvin Fig. 2 of the drawing. When the holder 25 and the `hydraulic mechanism assembled thereon is at the point along the drillpipe at which itis desired to secure the drill pipe protector, the hydraulic means, is operatedto slide the holder relative to the base I2, allowing the base to contract and closely grip the section of drillpipe 21. 'Ihe holder 25 and itsvassembled hydraulic mechanismis then-passed over the protector and removed from the end of the drill pipe section. During this operation, since the holder 25 is in frictional engagement with the, lower flange I'I after the upper flange I'Ihas ybeen deposited on the drill pipe, the'neck I8 is stretched to its full length by the downwardly moving holder 25, re-

moving any folds that may have been present a'meter larger than the outside diameter of the flanges I 'I when the base is in position Aupon the drill pipe section, is then passed over the base I2 until the spinner I3 mounted upon it is 1ongitudinally opposite the slot or groove I4, the hydraulic mechanism associated with the holder l26 isoperated to deposit the spinner I3 on the base with its endfaces 22 opposite the end'walls or shoulders 24 of the base and with its bore surface 20 in close proximity to the outer surkfacets of the neck ls. The length ofthe spinner'l3 relative to the groove I4is such as to provide clearance spaces 28 to allow a small end play between it and the flanges I'Iand theddiameter of its bore relative to the surface of the neck is such as to provide a clearance space'29 to allow` a smallradial play between the spinner and the neck I8. The outside diameter? ofthe spinner isk somewhat greater than-,the outside diameter of the flanges I'I so that when the protector; contacts the sidewalls or 'casing of the well, it is the spinner which receives'the blow rather than the flanges I1. l, l; While the mud fluid used in the drilling operbetween the spinner andthe base, the abrasive solid materialsof the'mud fluid will not apprei ciablycutV away either the' spinner orthe base,

t als-tarts because of the resilient character offthese bodies;`

Th bas tightly fitting" upon the drill lpipe 121,' i

ofthe other hand, preventsentrance` 'offanyofV the mudlfluid `between the Vbase `andlfhe pipe Wallsfof thepipesection. The base IZ-not only provides an excellent `bearing 'surface upon which the spinner rotates, but by reasonof its integrally formed end flanges, retains the spinner,` longitudinally in place `upon the pipeisections;`

The laminated' character of the base gives it laitighterl'grip upon the lpipe, fortifiesboth the flanges and the neck against laceration and ties the flanges 'strongly tov theinnermost laminations of the base whichfextend through the o neck,` preventing separation of the iianges from the neck and insuring retention of the spinner "in proper position longitudinally of the base.

While the base is preferably formed as hereinabove described, it is apparent that it need not be laminated in structure and that it may t Aeven be made of other than rubber or resilient to thesurface ofthe pipe section 'radiallyfbeneath the-rotating element, and means `for pre` venting endwise movement of the rotatingiele-f ment on `the drill pipe. The invention is not to be limited to any s-pecific embodiment thereof, but is to be given the scope defined bythe appended claims. l i Iclaim asmy invention: e f y l. In a drill 4pipe protector, the combination of: a first hollow' cylindricalbody `of rubber or like resiliently compressible material adapted to be a iirst hollow cylindrical body of rubber or like material without losing some of the advantages w of this invention. It also need not be a onepiece body, but may be made `of two semicircular halves or of other sections suitably secured toi form a cylindrical bearing member.

Figs. 9, 10, and 11 illustrate other forms which i the invention may take. These forms while not presenting all of the advantageous features of of the invention, still have some of the advantages of the invention which are not present in drill pipe protectors as at present known.

In Fig. 9 neck |8d is aseparate cylindrical body not integrally or otherwise connected `to iianges lla. A spinner |3a is rotatably mounted uponthe neck I8a. While the spinner |3a should be made of rubber or other resilient material, it is apparent that the neck |8a and flanges lla may be made of other` than resilient material, the one requisite being `that the neck |80. have a surface contact with the drill pipe 21a to prevent access of the mud fluid to the joint between the neck and drill pipe section.

In Fig. 10 a base IZb is shown as having a central annular ridge l'lb which fits within a slot l4b formed on the bore surface of a spinner |3b. The pipe section is protected from cut-` ting action of the' mud fluid and the spinner is retained in position longitudinally of the pipe section.

In Fig. 11 a spinner I3c is provided at its ends with insert bearing rings 3'0 secured to the spinner I3c by bolts 3| or any other suitable means.'

These bearings may be of steel or a materialespecially adapted for use in bearings. The bearing rings 30 slidably engage the outer surface of a pipe section 21e preventing access of mud.

fluid to a clearance chamber 32 between the spinner I3c and pipe 21e and each ring 30 also having an end thrust engagement with a stationary ring 33 of steel or suitable bearing metal disposed on the pipe 21e to prevent endwise movement of the spinner 13o `on the drill pipe section 21c. The rings 33 may be split rings arranged for ready securement to the pipe.

It will beapparent from the above description of one embodiment of the invention and of several modifications thereof, that the invention may have many other embodiments. Its essential features are a cylindrical resilient contact element rotatably mounted with respect to `the drill pipe, means associated with the mounting for preventing access of the mud fluidV resiliently compressible material `for stationary mounting on a drill pipe with its bore surface in fluid-tight contactwith said pipe; a second hollow cylindrical body of rubber or like resiliently compressible material adapted to be rotatably and concentrically mounted on said mounted rst body, the bore surface portion of said mounted second body and the peripheral surface portion of said mounted first body being of rubber or like resiliently compressible material and in rotative contact With each other; and means for retaining said second body endwise on said mounted first body.

3. The combination defined in claim 2 in which said rst cylindrical body is formed of one piece of a relatively stretchable material and normally of an inside diameter substantially smaller than the outside diameter of the drill pipe upon which it is to be used and upon whichit is thereby 1 adapted to be secured by first expanding it and then shrinking it on said drill pipe, and in which said second body is of substantially harder and less stretchable material thansaid` first body whereby it will better resist abrasion against the sides of a well.

4. In a drill pipe protector, the combination of a rst hollow cylindrical body of rubber or like resiliently compressible material for stationary mounting on a drill pipe with itsbore surface in huid-tight contact with said pipe; and a second hollow cylindrical body of rubber or like resiliently compressible material adapted to be concentrically and rotatably mounted on said mounted first body and secured against longitudinal vdisplacement from said mounted first body, the` which it is thereby adapted to be secured by first expanding it and then shrinking it on said drill pipe, said second body being oi substantially harder and less stretchable material than said first body whereby it will better resist abrasion against the sides of a well.

5. In a drill pipe protector, the combination of:`

a first hollow cylindrical body of `rubber or like resilientlyfcompressiblematerial adapted to be immova-blyl secured upon a 'drill pipe in concentric relation thereto; a second hollow cylindrical body of'rubber or like resilientlycompressible material adaptedto be rotatably mounted on said secured Iirsil body withv an appreciable radial clearance therebetween permitting limited eccentric movement of said second body with respect lto said secured first body,` the bore surface portion of said mounted second body and theperipheral surface portion of said secured rst body being of rubber orl like resilen-tls7 compressble material and in rotative contact with each other; and means for retaining said second body endwise upon said secured rst body While permitting said limited eccentric movement. ,n

6. In a drill pipe protector, the combination of:

arrst hollow; cylindrical body of rubberl or. like material adapted' to be mounted on a.. drillfpipe: a second hollow cylindrical bodyoi rubber orlike material. adapted to be; concentricaily and rotatably mountedy on, said mounted rst body with anfappreciable radial clearance therebetween permitting limited eccentric movement of saidsecvond body e-ndwise: on saidmounted first body,

said means beingadapted tofpermit limitedzendwise play of said second body. l r n A t l l WALTER Gu L. SMITH.V 

